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// Copyright (C) 2017 Caio Lima. All rights reserved.
// This code is governed by the BSD license found in the LICENSE file.
/*---
description: Mapped arguments property descriptor change to non-configurable and non-writable
info: |
Mapping just stop working when property is set to non-writable. Change the
descriptor using [[DefineOwnProperty]] to {configurable: false}, set arguments[0] = 2
and then change property descriptor to {writable: false}.
The descriptor's value need to be the one set before the property be
configured as {writable: false}.
flags: [noStrict]
esid: sec-arguments-exotic-objects-defineownproperty-p-desc
includes: [propertyHelper.js]
---*/
function fn(a) {
Object.defineProperty(arguments, "0", {configurable: false});
arguments[0] = 2;
Object.defineProperty(arguments, "0", {writable: false});
assert.sameValue(a, 2)
verifyProperty(arguments, "0", {
value: 2,
writable: false,
enumerable: true,
configurable: false,
});
// Postcondition: Arguments mapping is removed.
a = 3;
verifyProperty(arguments, "0", {
value: 2,
writable: false,
enumerable: true,
configurable: false,
});
}
fn(1);
reportCompare(0, 0);